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Environmental Problems and Health Risks
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Environmental Problems and Health Risks
Ashok KumarSchool of Biotechnology
Banaras Hindu University
Man and Environment: DEPENDENCE and INTERACTIONS
Compounds Dependence Spill off
Air Oxygen Wastes
Water EnergyLife Support
Soil Raw materials PollutantsMinerals Soil, WaterHabitat
Light ? Energy ?
Environment in ActionEnvironment in Action
Environment in ActionEnvironment in Action
Environment
Processes (Biotic and Abiotic)
Transformation
New Products (Good and Bad)
Damage to Environment (By bad one)
Repair (up to a limit)
Regain the originality
End point of Repair: The origin of Problems
Major Environmental Problems(South East Asia)
• Industrial Effluents
• Man made chemicals
• Natural agents
Most Abundant and common
Arsenic
Nitrate
Uranium
Arsenic poisoning is thought to be responsible for the deaths of some well known historical figures such as:
– Claudius– Pope Pius III and
Clemente XIV – Charles Francis
Hall – Napoleon
As: A Global problem
• 200 million people worldwide are at risk to As exposure (NRC, 2001)
• Several regions in the World are above the WHO’s maximum permissible limit. These include:- Bangladesh - Cambodia- India - Vietnam- China - Thailand- Argentina - U.S.- Chile - Nepal- Mexico - Ghana- Taiwan
http://www.who.int/mediacentre/factsheets/fs210/en/index.html
Arsenic pollution in the world
• Several nations in the world such as Argentina, Australia, Bangladesh, Chile, China, Hungary, India, Mexico, Peru, Thailand, and the U.S. have shown concentrations higher than the guideline value of 10 ug/L of the WHO.
• Adverse health effects from arsenic exposure have been documented in China, Bangladesh, India (West Bengal), and the USA.
• Currently, the worst problem exists in Bangladesh and West Bengal (India) where millions are being exposed to unhealthy amounts of arsenic through drinking water.
Features of As
• More than 20 arsenic species are present in nature
• Various arsenic species can be metabolized
• Different arsenic species have dramatically different toxicities
Natural Arsenic Levels
Crystalline Rock
Soil
Ground Water
Surface Water
Avg. 2 ppm
1-40 ppm
0.01 – 800 ppbAs high as 40,000 in hot springs
2.38 – 65 ppbAs high as 22,000 in river water
Health Effects
• Keratosis
Cancers Associated with Exposure to Arsenic in Drinking Water
• Skin
• Bladder
• Lung
• Kidney
• Liver
• Prostate
Source of Energy
Solar radiation on the Earth’s surface
Good & Bad Effects of SunlightGood & Bad Effects of Sunlight
Photosynthesis
Vitamin Dsynthesis
Vision
Kills pathogens
Phototherapy
Warmth
Pre-Cancer
Phototosensitivity
Cataracts
Cancer
Sunburn
Premature Aging
Immune systemchanges
BADGOOD
What Prevents Bad Effects of Solar Radiation
Layers of the Atmosphere35
30
25
20
15
10
5
50 10 15 20 25
Stratospheric Ozone(The Ozone Layer)
Tropospheric Ozone
“Smog” Ozone
Ozone Amount
Alti
tude
(K
ilom
eter
s)
“Good Ozone”
“Bad Ozone”
“Good “ and “Bad” Ozone
• Stratospheric “Good” Ozone: absorbs incident UV radiation.
• Ground-level “Bad” Ozone: high levels toxic to living systems.
Is UV Radiation on Increase?
Ozone Layer Depleting Chemicals
• chlorofluorocarbons (CFCs)
• carbon tetrachloride (CCl4)
• methyl chloroform (CH3CCl3)
• hydrochloric acid (HCl)
• methyl chloride (CH3Cl)
• methyl bromide(CH3Br)
Supersonic Jet & CFC Release
Global Ozone Field
Ozone Hole
Impacts of Ozone Depletion
• Increase in UV-B Radiation
• Global warming
Ultraviolet Radiation - UV
What is Ultraviolet Radiation?
Ultraviolet Radiation - UV
1.1. UV-A (320 400 nm)UV-A (320 400 nm)—causes skin aging & wrinkles. Used in tanning beds. Colors skin and gives false sense of protection from the sun. UVA rays pass effortlessly through the ozone layer.
Ultraviolet Radiation - UV
2.2. UV- B (280-320 nm)UV- B (280-320 nm)—causes sunburns, cataracts, immune system damage, skin cancer. Melanoma may be associated with severe UVB sunburns occurring before the age of 20. Most UVB rays are absorbed by the ozone layer.
Ultraviolet Radiation - UV
3.3. UV- C (200-280 nm)UV- C (200-280 nm)—these rays are the most dangerous. Fortunately, these rays are blocked by the ozone layer and don’t reach the Earth.
Another View of Sun
Ultraviolet Radiation - UV
Even on cloudy, cool, or overcast days, UV rays travel through the clouds and reflect off sand, water, snow, and even concrete.
Clouds and pollution don’t filter out UV rays, and can give a false sense of protection.
This “invisible sun” can cause unexpected sunburn and skin damage.
UV Exposure & Health
• Eye: Cataracts, universal problemEye: Cataracts, universal problem
• Even low amounts of sunlight can Even low amounts of sunlight can increase the risk of eye disorders.increase the risk of eye disorders.
• UVB damage to the eyes is cumulative, UVB damage to the eyes is cumulative, so it is never too late to start protecting so it is never too late to start protecting your eyes.your eyes.
Effects of UV Exposure
Skin Damage
Effects of UV Exposure
• There are about 1.3 million new There are about 1.3 million new cases of skin cancer in the U.S. cases of skin cancer in the U.S. each year, resulting in about 9,800 each year, resulting in about 9,800 deaths.deaths.
• Melanoma is one type of skin Melanoma is one type of skin cancer. It is the most common cancer. It is the most common cancer among women between the cancer among women between the ages of 25 and 29.ages of 25 and 29.
Effects of UV Exposure
• Scientists believe sunburns can alter Scientists believe sunburns can alter the body’s immune system for up to 24 the body’s immune system for up to 24 hours after exposure to the sun.hours after exposure to the sun.
• Repeated overexposure to UV radiation Repeated overexposure to UV radiation can cause more damage to the body’s can cause more damage to the body’s immune system, even in people with immune system, even in people with dark skin.dark skin.
UV Health Effects
• Short Term overexposure to UV-B:– UV-B causes sunburn (erythema)
– Sunburn can prevent your body from eliminating heat efficiently and can contribute to heat stress
• Long Term overexposure to UV-B:– Several severe sun burns linked to melanoma
– One person dies of skin cancer per hour in the U.S.
– Sustained exposure linked to squamous and basal skin cancers – non lethal
– Cataracts of eyes
• Long Term overexposure to UV-A:– Aging of skin
– Loss of elasticity (leathery look)
• Small amounts of UV radiation needed for Vitamin-D
Protection to UV-B Exposure
Guidelines for Protection
Eye Protection
Guidelines for Protection
Tanning Protection
Guidelines for Protection
Protective Clothing
Indirect Effects Having Effects on Human survival (Agricultural Productivity)
N fertilizer factory in Rice-field (cyanobacteria)
Rice-field
Rice-field
Anabaena
Calothrix
Scytonema
N. commune
UV-B effects on Ultrastructure of Cell
UV-B effects and loss of photosynthetic pigments
Effects of UV-B on total protein profile
Gene Expression with UV-B
• Gene expression in Synechocystis sp. PCC 6803 [----------------------------------------------]
3168 (ORFs)
DNA Microarray
UV-B Dose Transcript Response Induction Repression20 µE m-2 S-1 (120 min) 20 min 55 (2 fold) 44 (2 fold)120 min 21 4060 µE m-2 S-1 (120 min) 146 159
PsaA & PsaB - about 20 fold repression after 2 h(for PS I)D1 processing protease (ctpA) - 2 to 3 fold increasePBS-apcA, B, C, E,
cpcA, B, C, D, G - Down regulation
Scytonemin as a photoprotective compound
0 min 5 min 10 min 15 min 20 min 25 min
Water Blooms
Concern for Human Health
1- Lakshmikund 2- Durgakund 3- Kandawa pond4- Laat Bhairov pond5- Pishach Mochan Kund
1
2
3
4
5
Polluted Pond
Why Concern for Human Health?
Presence of Toxic Cyanobacterium • Over growth of Microcystis aeruginosa bloom• Shows allelopathic effects• Appears due to eutrophication
Health Concern• Produces hepatotoxin• Microcystin a heptapeptide having MW of 909 to 1067 dalton• Very stable and not easily biodegradable• Dose more lethal than cobra toxin• Released in pond water• Killings of human, pets, fishes etc. reported
ColonyMorphology
BIOASSAYS
Survival (LD50)
Circulatory complications
Liver morphology
Peripheral Blood Supply
Peripheral Blood Supply
IP
100 μl Cell freecrude extract (1.5 mg mcyt)
Loss of blood Supply
Control
Treated
Normal blood supply
Control
10.31% increasein %L/B ratio
Blood pooling andleakage of blood
capillaries
100 μl Cell freecrude extract(1.5 mg mcyt)
IP
Remedial Approach- 1
RawMaterials
Process Waste RECOVERYOf valuable compounds
Water EnergyRECYCLING
New Products
The Five R Policies:
• Process modifications aimed at the reduction of waste• Feedstock substitutions seeking the replacement of toxic or hazardous raw materials for more environment-friendly inputs 3. Efficient use of water, energy or inputs by means of reuse and/or recovery practices4. Good housekeeping and management practices, applying the reuse and/or recovery practices
Remedial Approach-II : Biotechnological Tools
Microbes: The Real Player• Natural selection• Genomic Modifications
Approaches• Isolate mutants • Modify cell functions/metabolism• Develop super strains by Rec-DNA Technology (GEM/GMO)
Purpose
• Use in Bioremediation• process development
Transposon
Genome
Plasmids
OCT
CAM - Camphor
OCT - Octane
XYL - Xylene
NAH - Naphthalene
DEVELOPMENT OF BACTERIAL STRAIN FOR DEGRADATION OF VARIOUS ORGANIC POLLUTANTS
Biotechnological Approach
Biotechnological Tools
CAM
C + T
XYL NAH
Biotechnological Approaches:
A. Bioremediation
• Can be done on site• Keeps site disruption to a minimum• Eliminates transportation costs and liabilities• Eliminates long-term liability• Uses biological systems, often less expensive• Can be coupled with other treatment techniques into a treatment train
B. Bioremediation Types;
1. Phytoremediation2. Microbial Systems: single strain/Microbial consortiums
For remediation of various pollutants/xenobionts such as industrial wastes,pesticides, heavy metals etc. Commercially available metal biosorbents BIOCLAM: Bacillus AlgaSORB: AlgaeBIO-FIX: Ulva sp., Spirulina, Saccharomyces cerevisiae, Lemna sp.
Commonly Used Genetically Engineered Microbes
Name Altered Trait Genets Transferred
Pseudomonas Altered pathway regula- Tol plasimid catabolic enzymestion
E. coli Metal removal from waste Metallothionein (human) waterE. Coli Polychlorinated biphenyl Entire pathway (Pseudomonas sp.)
metabolism
In-vivo Engineering of Bacteria for the Degradation of Xenobiotics and Toxic Wastes
Bacterium Substrate
Pseudomonas cepacia 2,4,5-trichlorophenylacetic acidP. Putida ChlorobenzenesAlcaligenes sp. Dechlorophenoxyacetic acid
mixed chlorophenols
Thanks